It has been an emotional week for Boris Johnson. It started by being grilled, gutted, filleted – whatever it was, it is what happens to a profoundly dead fish– by Eddie Mair. It ended with a YouGov poll, which found that if Boris took over as Tory leader, the two biggest parties would be level-pegging on 37% each, not least because the London mayor would lure one third of Ukip supporters back into the fold. Can Boris take heart from his Teflon-coated ability to stay connected to the very people who don't, traditionally, like politicians? Or should he end his own long-running psychodrama with his younger political brother David Cameron and beetle off to head an international charity in America? Do, in other words, what David Miliband did? There are many advantages to charitable work at this stage in Boris's career. First, it would confound the puritans, on right and left, who claim to detect a heat-seeking missile lurking beneath the floppy-haired, self-deprecating shambolic exterior. Second, Boris's many gifts would surely help a lost and forgotten charitable cause, with his attention to detail, ability to delegate and penchant for attracting publicity. But third, it is surely the right thing to do. As Miliband senior himself said, having taken so much from his privileged life, it's long past time to give something back. Boris knows that as long as he stays, he can only damage Mr Cameron's chances of a second term. And Boris definitively leaving the political scene would be good for their relationship. It would surely get easier.